Methods We used longitudinal data from a nationally representative, diverse sample of 13 701 adolescents followed into adulthood
to investigate whether associations between SES mobility categories (educational attainment reported by individuals as adults
and by their parents during adolescence) and body mass index (BMI) measured in adulthood varied by immigrant generation. Weighted
multivariable linear regression models were adjusted for age, sex, race/ethnicity and immigrant generation.

Results Among first-generation immigrants, although parental education was not associated with adult BMI, an immigrant's own education
attainment was inversely associated with BMI (β=−2.6 kg/m2; SE=0.9, p<0.01). In addition, upward educational mobility was associated with lower adult mean BMI than remaining low SES
(β=−2.5 kg/m2; SE=1.2, p<0.05). In contrast, among US-born respondents, college education in adulthood did not attenuate the negative association
between parental education and adult BMI. Although an SES gradient emerged in adulthood for immigrants, remaining low SES
from adolescence to adulthood was not associated with loss of health advantage relative to US-born respondents of US-born
parents of similar SES.

Conclusions Immigrants were able to translate higher SES in adulthood into a lower adult mean BMI regardless of childhood SES, whereas
the consequences of lower childhood SES had a longer reach even among the upwardly mobile US born.